The late sodium current (INaL) is a sustained component of the fast Na+ current of cardiac myocytes and neurons. Many common neurological and cardiac conditions are associated with abnormal INaL enhancement, which contributes to the pathogenesis of both electrical and contactile dysfunction in mammals. See, for example, Pathophysiology and Pharmacology of the Cardiac “Late Sodium Current”, Pharmacology and Therapeutics 119 (2008) 326-339. Accordingly, compounds that selectively inhibit INaL in mammals are useful in treating such disease states.
One example of a selective inhibitor of INaL is RANEXA®, a compound approved by the FDA for the treatment of chronic stable angina pectoris. RANEXA® has also been shown to be useful for the treatment of a variety of cardiovascular diseases, including ischemia, reperfusion injury, arrhythmia, unstable angina, and diabetes. It would be desirable to provide novel compounds that selectively inhibit INaL in mammals and that have the same selectivity over peak INa inhibition as RANEXA®.